Plotting the diagram of given data we have,
Now to find locus, let centre be (h,k). According to question
∣OM∣=∣ON∣ distance
⇒∣h∣=2∣h+k∣
squaring both sides we get
⇒2h2=(h+k)2
⇒2h2=h2+k2+2hk
Replacing h with x & k with y we get
2x2=x2+y2+2xy
⇒x2−y2=2xy